... to put in your backpack during traveling or exercising2.Compatible with laptop, iPod,MP3,MP4,MP5,cellphone.3. Dynamic ... portable, easy to carry.5.In-built lithium battery with high power capacity6.Matching all audio devices. Technical Specification ... 5 mm audio input interfaceHeadphone output interfacestandard 3.5 mm headphone jackMusicMP3 formatHorn1.5 inches, impedance seems Ω 4SNR80 dBFrequency ...